The network bottleneck mentioned in the paper, existing solutions indeed warrant reflection.

AmericanFortress has developed a patent-pending post-quantum signature scheme, aiming to implement a defensive freeze on Inactive and Dormant wallets through backward-compatible soft forks, protecting approximately 1.1 million Bitcoins and nearly 5 million idle Bitcoins, worth about $400 billion. Post-governance funds will be protected. The company completed $8 million in seed funding and published a paper highlighting the network performance bottlenecks present in existing post-quantum experiments.